package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetMealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.time.LocalDateTime;
import java.util.List;

@Service
public class ShoppingCartServiceImpl implements ShoppingCartService {

    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetMealMapper setMealMapper;

    /**
     * 添加购物车
     * @param shoppingCartDTO
     */
    @Transactional
    public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        // 判断当前加入购物车的商品是否存在
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        Long userId = BaseContext.getCurrentId();
        shoppingCart.setUserId(userId);

        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        // 如果存在，则将商品的数量加一
        if (list != null && !list.isEmpty()) {
            ShoppingCart cart = list.get(0);
            cart.setNumber(cart.getNumber() + 1);
            shoppingCartMapper.updateNumberById(cart);
        } else {
            // 如果不存在，则将商品加入到购物车中
            // 判断当前加入到购物车的是菜品还是套餐
            Long dishId = shoppingCart.getDishId();
            Long setmealId = shoppingCart.getSetmealId();
            if (dishId != null) {
                // 将菜品加入到购物车
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setImage(dish.getImage());
                shoppingCart.setAmount(dish.getPrice());
            } else if (setmealId != null) {
                // 将套餐加入到购物车
                Setmeal setmeal = setMealMapper.getById(setmealId);
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.addShoppingCart(shoppingCart);
        }


    }

    /**
     * 查看购物车
     * @param userId
     * @return
     */
    public List<ShoppingCart> list(Long userId) {
        ShoppingCart shoppingCart = new ShoppingCart();
        shoppingCart.setUserId(userId);
        return shoppingCartMapper.list(shoppingCart);
    }

    /**
     * 清空购物车
     * @param userId
     */
    public void cleanShoppingCart(Long userId) {
        shoppingCartMapper.cleanShoppingCart(userId);
    }

    /**
     * 从购物车中删除一个商品
     * @param shoppingCartDTO
     */
    public void subOne(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        shoppingCart.setUserId(BaseContext.getCurrentId());

        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        if (list != null && !list.isEmpty()) {
            shoppingCart = list.get(0);
            Integer number = shoppingCart.getNumber();
            if (number == 1) {
                // 当前商品在购物车中的数量为1，直接删除
                shoppingCartMapper.deleteById(shoppingCart.getId());
            } else {
                // 数量不为1，将数量减1，更新商品数据
                shoppingCart.setNumber(shoppingCart.getNumber() - 1);
                shoppingCartMapper.updateNumberById(shoppingCart);
            }
        }
    }
}





